Ultrasonic surgical instruments, including both hollow core and solid core instruments, are used for the safe and effective treatment of many medical conditions. Ultrasonic surgical instruments, and particularly solid core ultrasonic surgical instruments, are advantageous because they may be used to cut and/or coagulate organic tissue using energy in the form of mechanical vibrations transmitted to a surgical end-effector at ultrasonic frequencies. Ultrasonic vibrations, when transmitted to organic tissue at suitable energy levels and using a suitable end-effector, may be used to cut, dissect, or cauterize tissue. Ultrasonic surgical instruments utilizing solid core technology are particularly advantageous because of the amount of ultrasonic energy that may be transmitted from the ultrasonic transducer through the waveguide to the surgical end-effector. Such instruments are particularly suited for use in minimally invasive procedures, such as endoscopic or laparoscopic procedures, wherein the end-effector is passed through a trocar to reach the surgical site.
Ultrasonic vibration is induced in the surgical end-effector by, for example, electrically exciting a transducer mounted at the proximal end of the ultrasonic instrument. The transducer may be constructed of one or more piezoelectric or magnetostrictive elements which are mounted in the instrument handpiece. Vibrations generated by the transducer are transmitted to the surgical end-effector via an ultrasonic waveguide extending from the transducer section to the surgical end-effector.
U.S. Pat. No. 5,810,859 illustrates an ultrasonic surgical instrument for surgical applications wherein the ultrasonic waveguide is fixed within an outer sheath by a pin through a hub. However, the device described in U.S. Pat. No. 5,810,359 is not designed to be disassembled, cleaned, or re-sterilized.
Reusable ultrasonic surgical instruments incorporating removable outer sheaths cleaning and sterilization have been used, for example, Ethicon Endo-Surgery's HARMONIC SCALPEL. The HARMONIC SCALPEL line includes a 10-millimeter diameter reusable ultrasonic surgical instrument which incorporates a removable outer sheath which attaches to the instrument handpiece.
Therefore, it would be advantageous to provide an ultrasonic surgical instrument that may be easily disassembled for cleaning and then reassembled for multiple uses. It would further be advantageous to provide a reusable ultrasonic surgical instrument, which may be assembled before sterilization to reduce instrument assembly time during a surgical procedure. It would further be advantageous to provide an easily assembled reusable ultrasonic surgical instrument sized small enough to fit within an 8-millimeter or smaller trocar. It would further be advantageous to provide an ultrasonic surgical instrument including a removable outer sheath wherein the outer sheath removably and rotateably engages the waveguide to facilitate connection and removal of the waveguide and outer sheath from the handpiece.